The present invention relates to a cardiac pacing system and more particularly to a system useful in treating both bradycardia and tachycardia type arrhythmias.
In certain patients, particularly those suffering from sinus node disease, the basic atrial action of the heart may exhibit arrhythmias of both the bradycardia and tachycardia types. Often, the hearts of such patients beat essentially normally with only occasional lapses in bradycardia, in which the heart beats too slowly to effect adequate blood circulation. Occasionally, however, the hearts of such patients will break into tachycardia where the heart beats at too high a rate. While some such tachycardia attacks may revert spontaneously or in response to pharmacologic treatment, other types may persist for almost indefinite periods which are very debilitating to the patient. Certain other patients suffer from periodic ventricular tachyarrhythmias which do not respond to medical treatment.
Among the several objects of the present invention may be noted the provision of atrial pacing apparatus which is useful in treating both bradycardia type and tachycardia type arrhythmias; the provision of such apparatus in which the initiation of a stimulating sequence appropriate for the treatment of tachycardia may be initiated by the patient; the provision of such a system in which a particular sequence of stimulations for treating tachycardia may be externally predetermined; the provision of such a pacing system which incorporates an implantable pacer which is itself effective in treating bradycardia type arrhythmias; the provision of such apparatus which is easy to use, is highly reliable, and is of relatively simple and inexpensive construction. Other objects and features will be in part apparent and in part pointed out hereinafter.